Uniformly Loaded Simple Beam
For Dimensional Lumber 2-4" thick

When specifying a beam or joist three things are usually considered;
First,is the beam strong enough that it doesn't fail in bending, by the fibers on the bottom being torn apart, a fiber failure.

Second, is the beam stiff enough that there will not be excessive deflection. A bouncy floor, cracked tile or plaster would be examples of this.

Third, is the beam strong enough that its fibers don't slip past one another, bend a magazine and watch the pages slide past one another. This is a horizontal shear failure.

INPUTS


Change these inputs to reflect your variables
The design values for the species and grades in the drop down list are for dimensional lumber 2-4" thick
Load on Beam(pounds) Duration of Load
Span of Beam (inches) Repetitive Member
Width of Beam Size
Depth of Beam Wet Service
Select Species and Grade Incised

RESULTS

Bending Deflection Horizontal shear
Max Moment (ft-lbs) Deflection (inches) Shear (PSI)
Section Modulus Required Max 1/360 (Floor) Section Required
Section Modulus Input Max 1/240 (Roof) Section Input
Section Modulus Pass/Fail Deflection Pass/Fail Shear Pass/Fail

Lumber Design Values


Base Design Values Adjusted for Duration of Load, Repetitive Member Use, Size Factor, Moisture, and Incising
Base Design Values Adjusted Design Values
Allowable Fiberstress in Bending (Fb)(psi) Adjusted Allowable Fiberstress in Bending (Fb')(psi)
Modulus of Elasticity (E or MOE)(million psi) Adjusted Modulus of Elasticity (E or MOE)(million psi)
Allowable Shear (Fv)(psi) Adjusted Allowable Shear (Fv')(psi)
Maximum Compression Perpendicular to Grain (psi) Adjusted Maximum Compression Perpendicular to Grain (psi)
Disclaimer: Use of the online calculators within this website is free. While every effort has been made to ensure the accuracy of the calculators published within this website, you choose to use them and rely on any results at your own risk. We will not, under any circumstances accept, responsibility or liability for any losses that may arise from a decision that you may make as a result of using these calculators.